Since the very beginnings of European integration, still within the framework of the European Coal and Steel Community, the Member States have been trying to establish the institutional structure of the community and the court has played a key role in the period of political process stoppage and is considered to be responsible for the constitutionalization of the legal order of the European Union . The Court of the European Union was established by the Treaty of Rome in 1957 and in 1989 it was added a new court called the First Instance Court, renamed to the General Court by the Lisbon Treaty. Its establishment did not extend the jurisdiction of the European Court, but until that time, the one-stage procedure went into two stages. Shortly after the establishment of a new court, it turned out that two courts are still insufficient to relieve the work of the European Court. Therefore, the Treaty of Nice and the Treaty of Lisbon provided for the possibility of establishing specialized courts at European level.